Recent years have witnessed practical use of a flat-panel display in various products and fields. This has led to a demand for a flat-panel display that is larger in size, achieves higher image quality, and consumes less power.
Under such circumstances, great attention has been drawn to an organic EL display device that (i) includes an organic electroluminescence (hereinafter abbreviated to “EL”) element which uses EL of an organic material and that (ii) is an all-solid-state flat-panel display which is excellent in, for example, low-voltage driving, high-speed response, and self-emitting.
An organic EL display device includes, for example, (i) a substrate made up of members such as a glass substrate and TFTs (thin film transistors) provided to the glass substrate and (ii) organic EL elements provided on the substrate and connected to the TFTs.
An organic EL element is a light-emitting element capable of emitting high-luminance light by low-voltage direct-current drive. The organic EL element has a structure in which a first electrode, an organic EL layer, and a second electrode are stacked in this order, and the first electrode is electrically connected to the TFT. As the organic EL layer, an organic layer having a structure in which a hole injection layer, a hole transfer layer, an electron blocking layer, a luminescent layer, a hole blocking layer, an electron transfer layer, an electron injection layer, and the like are stacked together is provided between the first electrode and the second electrode.
A full-color organic EL display device typically includes, as sub-pixels aligned on a substrate, organic EL elements including light emitting layers of red (R), green (G), and blue (B). The full-color organic EL display device carries out color-image display by, with use of TFTs, selectively causing the organic EL elements to each emit light with a desired luminance.
In order to produce an organic EL display device, it is therefore necessary to form, for each organic EL element, a luminescent layer of a predetermined pattern made of an organic luminescent material which emits light of the colors. A layer that is not required to be patterned in shapes for respective organic EL elements is formed collectively in an entire pixel region constituted by the organic EL elements.
Formation of a luminescent layer of a predetermined pattern is performed by a method such as (i) a vacuum vapor deposition method, (ii) an inkjet method, and (iii) a laser transfer method. The production of, for example, a low-molecular organic EL display (OLED) often uses a vapor deposition method.
The vacuum vapor deposition method uses a mask (referred to also as a shadow mask) provided with openings of a predetermined pattern. The mask is fixed in close contact with a vapor-deposited surface of a substrate which vapor-deposited surface faces a vapor deposition source. Then, vapor deposition particles (film formation material) are injected from the vapor deposition source so as to be deposited on the vapor-deposited surface through openings of the mask. This forms a thin film of a predetermined pattern. The vapor deposition is carried out for each color of a luminescent layer (This is called “selective vapor deposition”).
Patent Literature 1 described below discloses a technique for (i) allowing a vapor deposition material to efficiently reach a to-be-treated substrate and (ii) causing the vapor deposition material to enter the to-be-treated substrate as perpendicularly as possible.
FIG. 15 is a cross-sectional view illustrating a configuration of a vapor deposition apparatus 100 disclosed in Patent Literature 1. The vapor deposition apparatus 100 includes a vapor deposition chamber 111. Inside the vapor deposition chamber 111, a substrate holder 119 holding a to-be-treated substrate 120 and a mask 131 is provided so as to be located in an upper part of the vapor deposition chamber 111. Inside the vapor deposition chamber 111, a vapor deposition source 112 for supplying vapor deposition particles to the to-be-treated substrate 120 is further provided so as to be located in a lower part of the vapor deposition chamber 111. The mask 131 is provided in place on a bottom surface (film formation surface) of the to-be-treated substrate 120.
The vapor deposition source 112 includes a crucible 140 filled with a vapor deposition material. The crucible 140 is provided directly below a center of the to-be-treated substrate 120, and carries out vapor deposition while the to-be-treated substrate 120 is fixed. The crucible 140 includes a heating container 141 to be filled with a vapor deposition material, a vapor flow nozzle 143a via which a vapor flow is emitted, and a tubular guide member 142 that (i) surrounds a path via which the vapor flow is emitted and (ii) is opened in a direction in which the vapor flow is emitted. The tubular guide member 142 has an inner circumferential surface formed of a flying direction controlling concave curved surface 142d that is a paraboloid for allowing vapor deposition particles having collided with the paraboloid to be reflected in a direction in which the vapor deposition particles are emitted. The vapor flow nozzle 143a is provided at a focal point of the flying direction controlling concave curved surface 142d. 
According to the configuration, the vapor deposition material heated in the heating container 141 is emitted, in the form of a vapor flow, via the vapor flow nozzle 143a, and is then deposited on the to-be-treated substrate 120. In this case, the path via which the vapor flow is emitted is surrounded by the flying direction controlling concave curved surface 142d, vapor deposition particles having flown in an oblique direction is reflected by the flying direction controlling concave curved surface 142d and then goes toward the to-be-treated substrate 120. Therefore, since the vapor flow to go toward the to-be-treated substrate 120 while having a small angle of divergence, it is possible to prevent the vapor deposition particles from adhering to an inner wall of the vapor deposition chamber 111. This makes it possible to allow the vapor deposition material to efficiently reach the to-be-treated substrate 120. Further, the vapor deposition particles can enter the to-be-treated substrate 120 as perpendicularly as possible.